An X-ray photographic equipment in the prior art is provided with a cassette holder wherein a cassette is to be loaded. The cassette holder is constructed to be moved to a radiographic position after a cassette has been loaded in a predetermined position of the cassette holder by an operator. Such cassettes have different sizes depending upon the size of a photographic object. The cassette holder is provided with a slidably movable frame, in order that a cassette of any size can be loaded in said predetermined position (for example, a center position) of the cassette holder. The operator manipulates the movable frame so to fix a cassette of any size in the interior of the cassette holder.
However, cassette loading operations and manipulations with use of the aforementioned cassette holder are unduly troublesome. To solve this problem a cassette automatic loading device without a cassette holder has been recently developed. In this automatic loading device, a cassette is disposed on a stage and there are provided positioning members independently driven from both sides of the disposed cassette, so that the cassette can be set in a determined position, and the stage is designed subsequently to be driven toward the photographic center position. According to the so defined automatic loading device, troubles caused upon effecting manipulation can be resolved, but it necessitates a driving device for moving the positioning members and another driving device for feeding the fixed cassette toward the radiographic position. This increases both the size and the weight of the equipment.